A new reflection x-ray microscope is in the process of final testing. Compared with earlier versions it has a resolving power previously unattainable because of inherent geometrical aberrations and little understood diffraction effects. A "figure" for its optical surfaces has been discovered which eliminates the asymmetrical image broadening which seriously limited the resolution of other reflection microscopes. X-ray focusing elements, both with and without an axis of symmetry, are under study for possible applications in biomedical research. Highly localized x-ray or neutron bombardment of single cells with well defined amounts of radient energy is now a distinct possibility for a basic study of radiation or repair processes. The increased resolution of the x-ray microscope now makes possible the determination, on a histo-chemical scale, of the atomic constitutents of tissue sections by coupling the microscope to a modern wavelength- dispersive system.